Research

Hormonal

Iron deficiency anemia blunts the efficacy of iodine supplementation in reducing goiter size, and concurrent iron supplementation restores this efficacy.

If you are in a region with goiter and suspect iron deficiency (anemia), iodine supplements alone may not shrink your thyroid. You likely need both iron and iodine. Consult a doctor for testing and dual supplementation.

GoodQualifiesHIGH confidence
Taken together, these data demonstrate that IDA blunts the efficacy of iodine prophylaxis while Fe supplementation improves the efficacy of oral iodized oil and iodized salt in goitrous children with IDA.
Michael Zimmermann et al. · Thyroid · 2002

Why this rating

Multiple randomized controlled trials and animal studies with consistent findings.

Source

The Impact of Iron and Selenium Deficiencies on Iodine and Thyroid Metabolism: Biochemistry and Relevance to Public Health

Michael Zimmermann et al. · Thyroid · 2002

DOI 10.1089/105072502761016494

narrative_reviewCited 343×
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DOI resolved against Crossref · corpus check 2026-06-10

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